1.Field of the Invention
This invention relates to recessed fixtures, and particularly to an improved fixture housing providing reduced airflow through the fixture without the use of additional sealing materials.
2. Description of Prior Art
As an energy conservation measure, many buildings are being constructed with a continuous vapor/air-flow barrier between conditioned (heated or cooled) spaces and unconditioned spaces (attics, wall cavities, etc.). The intent of the barrier is to retain conditioned air within the building""s outer envelope thereby reducing heating/cooling energy costs and to reduce the seepage of moisture into unconditioned spaces where condensation would damage materials. To meet this demand, it is becoming increasingly popular for recessed fixtures, such as recessed lighting fixtures, to be constructed with sealed housings to reduce airflow through the fixture. The Model Energy Code, Washington State Energy Code and many local ordinances require lighting fixtures with sealed housings that comply with prescribed leakage testing conducted in accordance with ASTM E283 xe2x80x9cStandard Test Method for Rate of Air Leakage Through Exterior Windows, Curtain, Walls, and Doorsxe2x80x9d standards. Additionally, many utilities offer rebate programs that promote sealed fixtures.
Further complicating sealed fixture design are requirements that fixture wiring be accessible at a junction box at each fixture for installation and maintenance purposes. Additionally, sealed fixtures rated for both ceiling and no-ceiling access must allow for a sealable opening in the housing to access the junction box from either the room side or the attic side of the fixture.
Commercially available sealed lighting fixtures are typically provided with gaskets, tapes and/or chemical sealant applied at the seams and holes in their housings. These sealing methods involve costly materials, complicate fixture assembly and may degrade over time and may not properly reseal.
To properly dissipate heat generated by a lamp (bulb), sealed recessed light fixtures require housings having sufficient volume. It is an industry standard to provide mounting bars to mechanically attach recessed fixtures to building structural members. These bars have length exceeding the width of the fixture mounting frame because the mounting frame is usually rectangular. Buildings have structural members spaced at distances prescribed by code. These factors sometimes conflict with each other and a fixture having maximal volume for heat dissipation has a mounting frame size which will not allow mounting bars to fit between building members.
Thus, it is an object of the present invention to provide a recessed fixture housing which does not require the use of gaskets, tapes or chemical sealant materials to create a sealed housing.
It is another object of the present invention to provide a recessed fixture which eliminates the need for additional components to achieve or surpass air-seal requirements as defined in ASTM E283.
It is a further object of the present invention to provide a recessed fixture housing in which the major components are designed with taper fits to allow the components to be pressed together in assembly to create an air-seal construction.
It is another object of the present invention to provide a sealed recessed fixture housing having a junction box which is accessible from either the room side of the fixture or the ceiling side of the fixture.
It is another object of the present invention to provide a recessed fixture frame for use with a housing of maximal size to be installed between building members arranged with minimal spacing.
Preferably, the recessed fixture housing of the present invention has a mounting frame section having a bottom and a raised wall extending therefrom, a housing wall section having a bottom rim, a top rim, and a side wall, said side wall having a junction box opening, a housing cover section having a top and a skirt depending therefrom, and a junction box. The mounting frame raised wall and housing wall section bottom rim are in an air-seal engagement, and the housing wall section bottom rim and said housing cover section skirt are also in an air-seal engagement. The junction box is received within said junction box opening; and the junction box and side wall are also in an air-seal engagement, said air-seal engagement sealing the junction box opening.
Additionally, the preferred recessed fixture frame of the present invention has a pair of mounting bar assemblies having bar sections, mounting stubs at the ends of the bar sections, tabs protruding from the bar section, and notches between each tab and mounting stub. Each mounting bar assembly is slidably attached to the mounting bar brackets of a mounting frame section. The mounting frame section is narrow enough to fit between a building""s structural members. The mounting frame section mounting bar brackets are inset from each side an amount sufficient to accommodate the mounting stubs and tabs of each mounting bar assembly between the building structural member and the bracket.